Question

Is it lawful for a privately held prom (such as one for homeschooled students) to prevent a female from attending because she's wearing a suit? Conditions: the prom has a strict dress code. Separate ones for male and female. The suit would conform with both.

Answer 1

No it is not

As a homeschooled student
I know from personal experiance that usually they are casual the boys wear suits if they like or not
Also trans/lesbian girls are allowed to express themselves through boys dress code if they please
Aulthough it is a bit of a controversy trans/lesbian girls are still sometimes suppressed to standard of a traditional women
Dress

It is not lawful